X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fopt%2Fldstopt.c;h=b67bafedd4434d2b3a5adb712e37c8dd5dc9c41d;hb=adefa68ae15e598e7c3e60cdf51dbf1d8b57b172;hp=84a52a4f8ac51937255c0464449644c06523e14c;hpb=75ae7b18e06eb779d052dd10bd43762ef19f7f75;p=libfirm diff --git a/ir/opt/ldstopt.c b/ir/opt/ldstopt.c index 84a52a4f8..b67bafedd 100644 --- a/ir/opt/ldstopt.c +++ b/ir/opt/ldstopt.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 1995-2007 University of Karlsruhe. All right reserved. + * Copyright (C) 1995-2008 University of Karlsruhe. All right reserved. * * This file is part of libFirm. * @@ -49,6 +49,12 @@ #include "opt_polymorphy.h" #include "irmemory.h" #include "xmalloc.h" +#include "irphase_t.h" +#include "irgopt.h" +#include "debug.h" + +/** The debug handle. */ +DEBUG_ONLY(static firm_dbg_module_t *dbg;) #ifdef DO_CACHEOPT #include "cacheopt/cachesim.h" @@ -57,7 +63,7 @@ #undef IMAX #define IMAX(a,b) ((a) > (b) ? (a) : (b)) -#define MAX_PROJ IMAX(pn_Load_max, pn_Store_max) +#define MAX_PROJ IMAX(IMAX(pn_Load_max, pn_Store_max), pn_Call_max) enum changes_t { DF_CHANGED = 1, /**< data flow changed */ @@ -72,19 +78,11 @@ typedef struct _walk_env_t { unsigned changes; /**< a bitmask of graph changes */ } walk_env_t; -/** - * flags for Load/Store - */ -enum ldst_flags_t { - LDST_VISITED = 1 /**< if set, this Load/Store is already visited */ -}; - /** A Load/Store info. */ typedef struct _ldst_info_t { ir_node *projs[MAX_PROJ]; /**< list of Proj's of this node */ ir_node *exc_block; /**< the exception block if available */ int exc_idx; /**< predecessor index in the exception block */ - unsigned flags; /**< flags */ unsigned visited; /**< visited counter for breaking loops */ } ldst_info_t; @@ -113,11 +111,11 @@ static unsigned master_visited = 0; /** * get the Load/Store info of a node */ -static ldst_info_t *get_ldst_info(ir_node *node, walk_env_t *env) { +static ldst_info_t *get_ldst_info(ir_node *node, struct obstack *obst) { ldst_info_t *info = get_irn_link(node); if (! info) { - info = obstack_alloc(&env->obst, sizeof(*info)); + info = obstack_alloc(obst, sizeof(*info)); memset(info, 0, sizeof(*info)); set_irn_link(node, info); } @@ -127,11 +125,11 @@ static ldst_info_t *get_ldst_info(ir_node *node, walk_env_t *env) { /** * get the Block info of a node */ -static block_info_t *get_block_info(ir_node *node, walk_env_t *env) { +static block_info_t *get_block_info(ir_node *node, struct obstack *obst) { block_info_t *info = get_irn_link(node); if (! info) { - info = obstack_alloc(&env->obst, sizeof(*info)); + info = obstack_alloc(obst, sizeof(*info)); memset(info, 0, sizeof(*info)); set_irn_link(node, info); } @@ -184,56 +182,26 @@ static unsigned update_exc(ldst_info_t *info, ir_node *block, int pos) */ static void collect_nodes(ir_node *node, void *env) { - ir_op *op = get_irn_op(node); + ir_opcode opcode = get_irn_opcode(node); ir_node *pred, *blk, *pred_blk; ldst_info_t *ldst_info; walk_env_t *wenv = env; - if (op == op_Proj) { - ir_node *adr; - ir_op *op; - - pred = get_Proj_pred(node); - op = get_irn_op(pred); + if (opcode == iro_Proj) { + pred = get_Proj_pred(node); + opcode = get_irn_opcode(pred); - if (op == op_Load) { - ldst_info = get_ldst_info(pred, wenv); + if (opcode == iro_Load || opcode == iro_Store || opcode == iro_Call) { + ldst_info = get_ldst_info(pred, &wenv->obst); wenv->changes |= update_projs(ldst_info, node); - if ((ldst_info->flags & LDST_VISITED) == 0) { - adr = get_Load_ptr(pred); - ldst_info->flags |= LDST_VISITED; - } - /* - * Place the Proj's to the same block as the - * predecessor Load. This is always ok and prevents - * "non-SSA" form after optimizations if the Proj - * is in a wrong block. - */ - blk = get_nodes_block(node); - pred_blk = get_nodes_block(pred); - if (blk != pred_blk) { - wenv->changes |= DF_CHANGED; - set_nodes_block(node, pred_blk); - } - } else if (op == op_Store) { - ldst_info = get_ldst_info(pred, wenv); - - wenv->changes |= update_projs(ldst_info, node); - - if ((ldst_info->flags & LDST_VISITED) == 0) { - adr = get_Store_ptr(pred); - ldst_info->flags |= LDST_VISITED; - } - - /* - * Place the Proj's to the same block as the - * predecessor Store. This is always ok and prevents - * "non-SSA" form after optimizations if the Proj - * is in a wrong block. - */ + * Place the Proj's to the same block as the + * predecessor Load. This is always ok and prevents + * "non-SSA" form after optimizations if the Proj + * is in a wrong block. + */ blk = get_nodes_block(node); pred_blk = get_nodes_block(pred); if (blk != pred_blk) { @@ -241,29 +209,36 @@ static void collect_nodes(ir_node *node, void *env) set_nodes_block(node, pred_blk); } } - } else if (op == op_Block) { + } else if (opcode == iro_Block) { int i; for (i = get_Block_n_cfgpreds(node) - 1; i >= 0; --i) { - ir_node *pred_block; + ir_node *pred_block, *proj; block_info_t *bl_info; + int is_exc = 0; + + pred = proj = get_Block_cfgpred(node, i); - pred = skip_Proj(get_Block_cfgpred(node, i)); + if (is_Proj(proj)) { + pred = get_Proj_pred(proj); + is_exc = get_Proj_proj(proj) == pn_Generic_X_except; + } /* ignore Bad predecessors, they will be removed later */ if (is_Bad(pred)) continue; pred_block = get_nodes_block(pred); - bl_info = get_block_info(pred_block, wenv); + bl_info = get_block_info(pred_block, &wenv->obst); - if (is_fragile_op(pred)) + if (is_fragile_op(pred) && is_exc) bl_info->flags |= BLOCK_HAS_EXC; else if (is_irn_forking(pred)) bl_info->flags |= BLOCK_HAS_COND; - if (get_irn_op(pred) == op_Load || get_irn_op(pred) == op_Store) { - ldst_info = get_ldst_info(pred, wenv); + opcode = get_irn_opcode(pred); + if (is_exc && (opcode == iro_Load || opcode == iro_Store || opcode == iro_Call)) { + ldst_info = get_ldst_info(pred, &wenv->obst); wenv->changes |= update_exc(ldst_info, node, i); } @@ -344,7 +319,7 @@ static ir_entity *find_constant_entity(ir_node *ptr) */ static long get_Sel_array_index_long(ir_node *n, int dim) { ir_node *index = get_Sel_index(n, dim); - assert(get_irn_op(index) == op_Const); + assert(is_Const(index)); return get_tarval_long(get_Const_tarval(index)); } /* get_Sel_array_index_long */ @@ -414,7 +389,9 @@ static void handle_load_update(ir_node *load) { /* a Load which value is neither used nor exception checked, remove it */ exchange(info->projs[pn_Load_M], mem); - exchange(load, new_Bad()); + if (info->projs[pn_Load_X_regular]) + exchange(info->projs[pn_Load_X_regular], new_r_Jmp(current_ir_graph, get_nodes_block(load))); + kill_node(load); reduce_adr_usage(ptr); } } /* handle_load_update */ @@ -458,9 +435,30 @@ static int can_use_stored_value(ir_mode *old_mode, ir_mode *new_mode) { } /* can_use_stored_value */ /** - * Follow the memory chain as long as there are only Loads - * and alias free Stores and try to replace current Load or Store - * by a previous ones. + * Check whether a Call is at least pure, ie. does only read memory. + */ +static unsigned is_Call_pure(ir_node *call) { + ir_type *call_tp = get_Call_type(call); + unsigned prop = get_method_additional_properties(call_tp); + + /* check first the call type */ + if ((prop & (mtp_property_const|mtp_property_pure)) == 0) { + /* try the called entity */ + ir_node *ptr = get_Call_ptr(call); + + if (is_Global(ptr)) { + ir_entity *ent = get_Global_entity(ptr); + + prop = get_entity_additional_properties(ent); + } + } + return (prop & (mtp_property_const|mtp_property_pure)) != 0; +} /* is_Call_pure */ + +/** + * Follow the memory chain as long as there are only Loads, + * alias free Stores, and constant Calls and try to replace the + * current Load by a previous ones. * Note that in unreachable loops it might happen that we reach * load again, as well as we can fall into a cycle. * We break such cycles using a special visited flag. @@ -484,22 +482,22 @@ static unsigned follow_Mem_chain(ir_node *load, ir_node *curr) { * This is only true in strong typed languages, not in C were the following * is possible a = *(ir_type1 *)p; b = *(ir_type2 *)p ... */ - if (get_irn_op(pred) == op_Store && get_Store_ptr(pred) == ptr && + if (is_Store(pred) && get_Store_ptr(pred) == ptr && can_use_stored_value(get_irn_mode(get_Store_value(pred)), load_mode)) { /* * a Load immediately after a Store -- a read after write. * We may remove the Load, if both Load & Store does not have an exception handler - * OR they are in the same block. In the latter case the Load cannot + * OR they are in the same MacroBlock. In the latter case the Load cannot * throw an exception when the previous Store was quiet. * * Why we need to check for Store Exception? If the Store cannot * be executed (ROM) the exception handler might simply jump into - * the load block :-( + * the load MacroBlock :-( * We could make it a little bit better if we would know that the exception * handler of the Store jumps directly to the end... */ if ((pred_info->projs[pn_Store_X_except] == NULL && info->projs[pn_Load_X_except] == NULL) || - get_nodes_block(load) == get_nodes_block(pred)) { + get_nodes_MacroBlock(load) == get_nodes_MacroBlock(pred)) { ir_node *value = get_Store_value(pred); DBG_OPT_RAW(load, value); @@ -517,26 +515,30 @@ static unsigned follow_Mem_chain(ir_node *load, ir_node *curr) { exchange( info->projs[pn_Load_X_except], new_Bad()); res |= CF_CHANGED; } + if (info->projs[pn_Load_X_regular]) { + exchange( info->projs[pn_Load_X_regular], new_r_Jmp(current_ir_graph, get_nodes_block(load))); + res |= CF_CHANGED; + } if (info->projs[pn_Load_res]) exchange(info->projs[pn_Load_res], value); - exchange(load, new_Bad()); + kill_node(load); reduce_adr_usage(ptr); return res | DF_CHANGED; } - } else if (get_irn_op(pred) == op_Load && get_Load_ptr(pred) == ptr && + } else if (is_Load(pred) && get_Load_ptr(pred) == ptr && can_use_stored_value(get_Load_mode(pred), load_mode)) { /* * a Load after a Load -- a read after read. * We may remove the second Load, if it does not have an exception handler - * OR they are in the same block. In the later case the Load cannot + * OR they are in the same MacroBlock. In the later case the Load cannot * throw an exception when the previous Load was quiet. * * Here, there is no need to check if the previous Load has an exception * hander because they would have exact the same exception... */ - if (info->projs[pn_Load_X_except] == NULL || get_nodes_block(load) == get_nodes_block(pred)) { + if (info->projs[pn_Load_X_except] == NULL || get_nodes_MacroBlock(load) == get_nodes_MacroBlock(pred)) { ir_node *value; DBG_OPT_RAR(load, pred); @@ -565,14 +567,18 @@ static unsigned follow_Mem_chain(ir_node *load, ir_node *curr) { exchange(info->projs[pn_Load_X_except], new_Bad()); res |= CF_CHANGED; } + if (info->projs[pn_Load_X_regular]) { + exchange( info->projs[pn_Load_X_regular], new_r_Jmp(current_ir_graph, get_nodes_block(load))); + res |= CF_CHANGED; + } - exchange(load, new_Bad()); + kill_node(load); reduce_adr_usage(ptr); return res |= DF_CHANGED; } } - if (get_irn_op(pred) == op_Store) { + if (is_Store(pred)) { /* check if we can pass through this store */ ir_alias_relation rel = get_alias_relation( current_ir_graph, @@ -580,11 +586,20 @@ static unsigned follow_Mem_chain(ir_node *load, ir_node *curr) { get_irn_mode(get_Store_value(pred)), ptr, load_mode); /* if the might be an alias, we cannot pass this Store */ - if (rel != no_alias) + if (rel != ir_no_alias) break; pred = skip_Proj(get_Store_mem(pred)); - } else if (get_irn_op(pred) == op_Load) { + } else if (is_Load(pred)) { pred = skip_Proj(get_Load_mem(pred)); + } else if (is_Call(pred)) { + if (is_Call_pure(pred)) { + /* The called graph is at least pure, so there are no Store's + in it. We can handle it like a Load and skip it. */ + pred = skip_Proj(get_Call_mem(pred)); + } else { + /* there might be Store's in the graph, stop here */ + break; + } } else { /* follow only Load chains */ break; @@ -596,14 +611,14 @@ static unsigned follow_Mem_chain(ir_node *load, ir_node *curr) { MARK_NODE(pred_info); } - if (get_irn_op(pred) == op_Sync) { + if (is_Sync(pred)) { int i; /* handle all Sync predecessors */ for (i = get_Sync_n_preds(pred) - 1; i >= 0; --i) { res |= follow_Mem_chain(load, skip_Proj(get_Sync_pred(pred, i))); if (res) - break; + return res; } } @@ -642,7 +657,7 @@ static unsigned optimize_load(ir_node *load) ir_node *mem = get_Sel_mem(ptr); /* FIXME: works with the current FE, but better use the base */ - if (get_irn_op(skip_Proj(mem)) == op_Alloc) { + if (is_Alloc(skip_Proj(mem))) { /* ok, check the types */ ir_entity *ent = get_Sel_entity(ptr); ir_type *s_type = get_entity_type(ent); @@ -654,11 +669,12 @@ static unsigned optimize_load(ir_node *load) exchange(info->projs[pn_Load_X_except], new_Bad()); info->projs[pn_Load_X_except] = NULL; + exchange(info->projs[pn_Load_X_regular], new_r_Jmp(current_ir_graph, get_nodes_block(load))); + info->projs[pn_Load_X_regular] = NULL; res |= CF_CHANGED; } } - } else if ((get_irn_op(skip_Proj(ptr)) == op_Alloc) || - ((get_irn_op(ptr) == op_Cast) && (get_irn_op(skip_Proj(get_Cast_op(ptr))) == op_Alloc))) { + } else if (is_Alloc(skip_Proj(skip_Cast(ptr)))) { /* simple case: a direct load after an Alloc. Firm Alloc throw * an exception in case of out-of-memory. So, there is no way for an * exception in this load. @@ -666,6 +682,8 @@ static unsigned optimize_load(ir_node *load) */ exchange(info->projs[pn_Load_X_except], new_Bad()); info->projs[pn_Load_X_except] = NULL; + exchange(info->projs[pn_Load_X_regular], new_r_Jmp(current_ir_graph, get_nodes_block(load))); + info->projs[pn_Load_X_regular] = NULL; res |= CF_CHANGED; } } @@ -677,7 +695,12 @@ static unsigned optimize_load(ir_node *load) /* a Load which value is neither used nor exception checked, remove it */ exchange(info->projs[pn_Load_M], mem); - exchange(load, new_Bad()); + if (info->projs[pn_Load_X_regular]) { + /* should not happen, but if it does, remove it */ + exchange(info->projs[pn_Load_X_regular], new_r_Jmp(current_ir_graph, get_nodes_block(load))); + res |= CF_CHANGED; + } + kill_node(load); reduce_adr_usage(ptr); return res | DF_CHANGED; } @@ -693,11 +716,17 @@ static unsigned optimize_load(ir_node *load) if (info->projs[pn_Load_X_except]) { exchange(info->projs[pn_Load_X_except], new_Bad()); info->projs[pn_Load_X_except] = NULL; + res |= CF_CHANGED; + } + if (info->projs[pn_Load_X_regular]) { + exchange(info->projs[pn_Load_X_regular], new_r_Jmp(current_ir_graph, get_nodes_block(load))); + info->projs[pn_Load_X_regular] = NULL; + res |= CF_CHANGED; } if (info->projs[pn_Load_res]) exchange(info->projs[pn_Load_res], new_node); - exchange(load, new_Bad()); + kill_node(load); reduce_adr_usage(ptr); return res | DF_CHANGED; } @@ -716,80 +745,86 @@ static unsigned optimize_load(ir_node *load) info->projs[pn_Load_X_except] = NULL; res |= CF_CHANGED; } + if (info->projs[pn_Load_X_regular]) { + exchange(info->projs[pn_Load_X_regular], new_r_Jmp(current_ir_graph, get_nodes_block(load))); + info->projs[pn_Load_X_regular] = NULL; + res |= CF_CHANGED; + } - if (variability_constant == get_entity_variability(ent) - && is_atomic_entity(ent)) { - /* Might not be atomic after - lowering of Sels. In this - case we could also load, but - it's more complicated. */ - /* more simpler case: we load the content of a constant value: - * replace it by the constant itself - */ - - /* no memory */ - if (info->projs[pn_Load_M]) { - exchange(info->projs[pn_Load_M], mem); - res |= DF_CHANGED; - } - /* no result :-) */ - if (info->projs[pn_Load_res]) { - if (is_atomic_entity(ent)) { - ir_node *c = copy_const_value(get_irn_dbg_info(load), get_atomic_ent_value(ent)); - - DBG_OPT_RC(load, c); - exchange(info->projs[pn_Load_res], c); - res |= DF_CHANGED; - } - } - exchange(load, new_Bad()); - reduce_adr_usage(ptr); - return res; - } else if (variability_constant == get_entity_variability(ent)) { - compound_graph_path *path = get_accessed_path(ptr); - - if (path) { - ir_node *c; - - assert(is_proper_compound_graph_path(path, get_compound_graph_path_length(path)-1)); - /* - { - int j; - for (j = 0; j < get_compound_graph_path_length(path); ++j) { - ir_entity *node = get_compound_graph_path_node(path, j); - fprintf(stdout, ".%s", get_entity_name(node)); - if (is_Array_type(get_entity_owner(node))) - fprintf(stdout, "[%d]", get_compound_graph_path_array_index(path, j)); - } - printf("\n"); - } - */ - - c = get_compound_ent_value_by_path(ent, path); - free_compound_graph_path(path); - - /* printf(" cons: "); DDMN(c); */ - + if (variability_constant == get_entity_variability(ent)) { + if (is_atomic_entity(ent)) { + /* Might not be atomic after + lowering of Sels. In this + case we could also load, but + it's more complicated. */ + /* more simpler case: we load the content of a constant value: + * replace it by the constant itself + */ + + /* no memory */ if (info->projs[pn_Load_M]) { exchange(info->projs[pn_Load_M], mem); res |= DF_CHANGED; } + /* no result :-) */ if (info->projs[pn_Load_res]) { - exchange(info->projs[pn_Load_res], copy_const_value(get_irn_dbg_info(load), c)); - res |= DF_CHANGED; + if (is_atomic_entity(ent)) { + ir_node *c = copy_const_value(get_irn_dbg_info(load), get_atomic_ent_value(ent)); + + DBG_OPT_RC(load, c); + exchange(info->projs[pn_Load_res], c); + res |= DF_CHANGED; + } } - exchange(load, new_Bad()); + kill_node(load); reduce_adr_usage(ptr); return res; } else { - /* We can not determine a correct access path. E.g., in jack, we load - a byte from an object to generate an exception. Happens in test program - Reflectiontest. - printf(">>>>>>>>>>>>> Found access to constant entity %s in function %s\n", get_entity_name(ent), - get_entity_name(get_irg_entity(current_ir_graph))); - printf(" load: "); DDMN(load); - printf(" ptr: "); DDMN(ptr); - */ + compound_graph_path *path = get_accessed_path(ptr); + + if (path && !ent->has_initializer) { + ir_node *c; + + assert(is_proper_compound_graph_path(path, get_compound_graph_path_length(path)-1)); + /* + { + int j; + for (j = 0; j < get_compound_graph_path_length(path); ++j) { + ir_entity *node = get_compound_graph_path_node(path, j); + fprintf(stdout, ".%s", get_entity_name(node)); + if (is_Array_type(get_entity_owner(node))) + fprintf(stdout, "[%d]", get_compound_graph_path_array_index(path, j)); + } + printf("\n"); + } + */ + + c = get_compound_ent_value_by_path(ent, path); + free_compound_graph_path(path); + + /* printf(" cons: "); DDMN(c); */ + + if (info->projs[pn_Load_M]) { + exchange(info->projs[pn_Load_M], mem); + res |= DF_CHANGED; + } + if (info->projs[pn_Load_res]) { + exchange(info->projs[pn_Load_res], copy_const_value(get_irn_dbg_info(load), c)); + res |= DF_CHANGED; + } + kill_node(load); + reduce_adr_usage(ptr); + return res; + } else { + /* We can not determine a correct access path. E.g., in jack, we load + a byte from an object to generate an exception. Happens in test program + Reflectiontest. + printf(">>>>>>>>>>>>> Found access to constant entity %s in function %s\n", get_entity_name(ent), + get_entity_name(get_irg_entity(current_ir_graph))); + printf(" load: "); DDMN(load); + printf(" ptr: "); DDMN(ptr); + */ + } } } } @@ -835,6 +870,7 @@ static unsigned follow_Mem_chain_for_Store(ir_node *store, ir_node *curr) { ir_node *value = get_Store_value(store); ir_mode *mode = get_irn_mode(value); ir_node *block = get_nodes_block(store); + ir_node *mblk = get_Block_MacroBlock(block); for (pred = curr; pred != store;) { ldst_info_t *pred_info = get_irn_link(pred); @@ -847,38 +883,40 @@ static unsigned follow_Mem_chain_for_Store(ir_node *store, ir_node *curr) { * However, if the mode that is written have a bigger or equal size the the old * one, the old value is completely overwritten and can be killed ... */ - if (get_irn_op(pred) == op_Store && get_Store_ptr(pred) == ptr && - get_nodes_block(pred) == block && + if (is_Store(pred) && get_Store_ptr(pred) == ptr && + get_nodes_MacroBlock(pred) == mblk && is_completely_overwritten(get_irn_mode(get_Store_value(pred)), mode)) { /* - * a Store after a Store in the same block -- a write after write. + * a Store after a Store in the same MacroBlock -- a write after write. * We may remove the first Store, if it does not have an exception handler. * * TODO: What, if both have the same exception handler ??? */ if (get_Store_volatility(pred) != volatility_is_volatile && !pred_info->projs[pn_Store_X_except]) { DBG_OPT_WAW(pred, store); - exchange( pred_info->projs[pn_Store_M], get_Store_mem(pred) ); - exchange(pred, new_Bad()); + exchange(pred_info->projs[pn_Store_M], get_Store_mem(pred)); + kill_node(pred); reduce_adr_usage(ptr); return DF_CHANGED; } - } else if (get_irn_op(pred) == op_Load && get_Load_ptr(pred) == ptr && + } else if (is_Load(pred) && get_Load_ptr(pred) == ptr && value == pred_info->projs[pn_Load_res]) { /* - * a Store of a value after a Load -- a write after read. - * We may remove the second Store, if it does not have an exception handler. + * a Store of a value just loaded from the same address + * -- a write after read. + * We may remove the Store, if it does not have an exception + * handler. */ if (! info->projs[pn_Store_X_except]) { DBG_OPT_WAR(store, pred); - exchange( info->projs[pn_Store_M], mem ); - exchange(store, new_Bad()); + exchange(info->projs[pn_Store_M], mem); + kill_node(store); reduce_adr_usage(ptr); return DF_CHANGED; } } - if (get_irn_op(pred) == op_Store) { + if (is_Store(pred)) { /* check if we can pass thru this store */ ir_alias_relation rel = get_alias_relation( current_ir_graph, @@ -886,10 +924,16 @@ static unsigned follow_Mem_chain_for_Store(ir_node *store, ir_node *curr) { get_irn_mode(get_Store_value(pred)), ptr, mode); /* if the might be an alias, we cannot pass this Store */ - if (rel != no_alias) + if (rel != ir_no_alias) break; pred = skip_Proj(get_Store_mem(pred)); } else if (get_irn_op(pred) == op_Load) { + ir_alias_relation rel = get_alias_relation( + current_ir_graph, get_Load_ptr(pred), get_Load_mode(pred), + ptr, mode); + if (rel != ir_no_alias) + break; + pred = skip_Proj(get_Load_mem(pred)); } else { /* follow only Load chains */ @@ -902,7 +946,7 @@ static unsigned follow_Mem_chain_for_Store(ir_node *store, ir_node *curr) { MARK_NODE(pred_info); } - if (get_irn_op(pred) == op_Sync) { + if (is_Sync(pred)) { int i; /* handle all Sync predecessors */ @@ -937,6 +981,7 @@ static unsigned optimize_store(ir_node *store) { /* follow the memory chain as long as there are only Loads */ INC_MASTER(); + return follow_Mem_chain_for_Store(store, skip_Proj(mem)); } /* optimize_store */ @@ -1018,7 +1063,7 @@ static unsigned optimize_phi(ir_node *phi, walk_env_t *wenv) return 0; pred = skip_Proj(pred); - if (get_irn_op(pred) != op_Store) + if (!is_Store(pred)) return 0; if (ptr != get_Store_ptr(pred) || mode != get_irn_mode(get_Store_value(pred))) @@ -1112,7 +1157,7 @@ static unsigned optimize_phi(ir_node *phi, walk_env_t *wenv) projM = new_rd_Proj(NULL, current_ir_graph, block, store, mode_M, pn_Store_M); - info = get_ldst_info(store, wenv); + info = get_ldst_info(store, &wenv->obst); info->projs[pn_Store_M] = projM; /* fifths step: repair exception flow */ @@ -1158,24 +1203,548 @@ static void do_load_store_optimize(ir_node *n, void *env) { case iro_Phi: wenv->changes |= optimize_phi(n, wenv); + break; default: ; } } /* do_load_store_optimize */ +/** A scc. */ +typedef struct scc { + ir_node *head; /**< the head of the list */ +} scc; + +/** A node entry. */ +typedef struct node_entry { + unsigned DFSnum; /**< the DFS number of this node */ + unsigned low; /**< the low number of this node */ + ir_node *header; /**< the header of this node */ + int in_stack; /**< flag, set if the node is on the stack */ + ir_node *next; /**< link to the next node the the same scc */ + scc *pscc; /**< the scc of this node */ + unsigned POnum; /**< the post order number for blocks */ +} node_entry; + +/** A loop entry. */ +typedef struct loop_env { + ir_phase ph; /**< the phase object */ + ir_node **stack; /**< the node stack */ + int tos; /**< tos index */ + unsigned nextDFSnum; /**< the current DFS number */ + unsigned POnum; /**< current post order number */ + + unsigned changes; /**< a bitmask of graph changes */ +} loop_env; + +/** +* Gets the node_entry of a node +*/ +static node_entry *get_irn_ne(ir_node *irn, loop_env *env) { + ir_phase *ph = &env->ph; + node_entry *e = phase_get_irn_data(&env->ph, irn); + + if (! e) { + e = phase_alloc(ph, sizeof(*e)); + memset(e, 0, sizeof(*e)); + phase_set_irn_data(ph, irn, e); + } + return e; +} /* get_irn_ne */ + +/** + * Push a node onto the stack. + * + * @param env the loop environment + * @param n the node to push + */ +static void push(loop_env *env, ir_node *n) { + node_entry *e; + + if (env->tos == ARR_LEN(env->stack)) { + int nlen = ARR_LEN(env->stack) * 2; + ARR_RESIZE(ir_node *, env->stack, nlen); + } + env->stack[env->tos++] = n; + e = get_irn_ne(n, env); + e->in_stack = 1; +} /* push */ + +/** + * pop a node from the stack + * + * @param env the loop environment + * + * @return The topmost node + */ +static ir_node *pop(loop_env *env) { + ir_node *n = env->stack[--env->tos]; + node_entry *e = get_irn_ne(n, env); + + e->in_stack = 0; + return n; +} /* pop */ + +/** + * Check if irn is a region constant. + * The block or irn must strictly dominate the header block. + * + * @param irn the node to check + * @param header_block the header block of the induction variable + */ +static int is_rc(ir_node *irn, ir_node *header_block) { + ir_node *block = get_nodes_block(irn); + + return (block != header_block) && block_dominates(block, header_block); +} /* is_rc */ + +typedef struct phi_entry phi_entry; +struct phi_entry { + ir_node *phi; /**< A phi with a region const memory. */ + int pos; /**< The position of the region const memory */ + ir_node *load; /**< the newly created load for this phi */ + phi_entry *next; +}; + +/** + * Move loops out of loops if possible. + * + * @param pscc the loop described by an SCC + * @param env the loop environment + */ +static void move_loads_out_of_loops(scc *pscc, loop_env *env) { + ir_node *phi, *load, *next, *other, *next_other; + ir_entity *ent; + int j; + phi_entry *phi_list = NULL; + + /* collect all outer memories */ + for (phi = pscc->head; phi != NULL; phi = next) { + node_entry *ne = get_irn_ne(phi, env); + next = ne->next; + + /* check all memory Phi's */ + if (! is_Phi(phi)) + continue; + + assert(get_irn_mode(phi) == mode_M && "DFS geturn non-memory Phi"); + + for (j = get_irn_arity(phi) - 1; j >= 0; --j) { + ir_node *pred = get_irn_n(phi, j); + node_entry *pe = get_irn_ne(pred, env); + + if (pe->pscc != ne->pscc) { + /* not in the same SCC, is region const */ + phi_entry *pe = phase_alloc(&env->ph, sizeof(*pe)); + + pe->phi = phi; + pe->pos = j; + pe->next = phi_list; + phi_list = pe; + } + } + } + /* no Phis no fun */ + assert(phi_list != NULL && "DFS found a loop without Phi"); + + for (load = pscc->head; load; load = next) { + ir_mode *load_mode; + node_entry *ne = get_irn_ne(load, env); + next = ne->next; + + if (is_Load(load)) { + ldst_info_t *info = get_irn_link(load); + ir_node *ptr = get_Load_ptr(load); + + /* for now, we cannot handle Loads with exceptions */ + if (info->projs[pn_Load_res] == NULL || info->projs[pn_Load_X_regular] != NULL || info->projs[pn_Load_X_except] != NULL) + continue; + + /* for now, we can only handle Load(Global) */ + if (! is_Global(ptr)) + continue; + ent = get_Global_entity(ptr); + load_mode = get_Load_mode(load); + for (other = pscc->head; other != NULL; other = next_other) { + node_entry *ne = get_irn_ne(other, env); + next_other = ne->next; + + if (is_Store(other)) { + ir_alias_relation rel = get_alias_relation( + current_ir_graph, + get_Store_ptr(other), + get_irn_mode(get_Store_value(other)), + ptr, load_mode); + /* if the might be an alias, we cannot pass this Store */ + if (rel != ir_no_alias) + break; + } + /* only pure Calls are allowed here, so ignore them */ + } + if (other == NULL) { + ldst_info_t *ninfo; + phi_entry *pe; + dbg_info *db; + + /* for now, we cannot handle more than one input */ + if (phi_list->next != NULL) + return; + + /* yep, no aliasing Store found, Load can be moved */ + DB((dbg, LEVEL_1, " Found a Load that could be moved: %+F\n", load)); + + db = get_irn_dbg_info(load); + for (pe = phi_list; pe != NULL; pe = pe->next) { + int pos = pe->pos; + ir_node *phi = pe->phi; + ir_node *blk = get_nodes_block(phi); + ir_node *pred = get_Block_cfgpred_block(blk, pos); + ir_node *irn, *mem; + + pe->load = irn = new_rd_Load(db, current_ir_graph, pred, get_Phi_pred(phi, pos), ptr, load_mode); + ninfo = get_ldst_info(irn, phase_obst(&env->ph)); + + ninfo->projs[pn_Load_M] = mem = new_r_Proj(current_ir_graph, pred, irn, mode_M, pn_Load_M); + set_Phi_pred(phi, pos, mem); + + ninfo->projs[pn_Load_res] = new_r_Proj(current_ir_graph, pred, irn, load_mode, pn_Load_res); + + DB((dbg, LEVEL_1, " Created %+F in %+F\n", irn, pred)); + } + + /* now kill the old Load */ + exchange(info->projs[pn_Load_M], get_Load_mem(load)); + exchange(info->projs[pn_Load_res], ninfo->projs[pn_Load_res]); + + env->changes |= DF_CHANGED; + } + } + } +} /* move_loads_out_of_loops */ + +/** + * Process a loop SCC. + * + * @param pscc the SCC + * @param env the loop environment + */ +static void process_loop(scc *pscc, loop_env *env) { + ir_node *irn, *next, *header = NULL; + node_entry *b, *h = NULL; + int j, only_phi, num_outside, process = 0; + ir_node *out_rc; + + /* find the header block for this scc */ + for (irn = pscc->head; irn; irn = next) { + node_entry *e = get_irn_ne(irn, env); + ir_node *block = get_nodes_block(irn); + + next = e->next; + b = get_irn_ne(block, env); + + if (header) { + if (h->POnum < b->POnum) { + header = block; + h = b; + } + } + else { + header = block; + h = b; + } + } + + /* check if this scc contains only Phi, Loads or Stores nodes */ + only_phi = 1; + num_outside = 0; + out_rc = NULL; + for (irn = pscc->head; irn; irn = next) { + node_entry *e = get_irn_ne(irn, env); + + next = e->next; + switch (get_irn_opcode(irn)) { + case iro_Call: + if (is_Call_pure(irn)) { + /* pure calls can be treated like loads */ + only_phi = 0; + break; + } + /* non-pure calls must be handle like may-alias Stores */ + goto fail; + case iro_CopyB: + /* cannot handle CopyB yet */ + goto fail; + case iro_Load: + process = 1; + if (get_Load_volatility(irn) == volatility_is_volatile) { + /* cannot handle loops with volatile Loads */ + goto fail; + } + only_phi = 0; + break; + case iro_Store: + if (get_Store_volatility(irn) == volatility_is_volatile) { + /* cannot handle loops with volatile Stores */ + goto fail; + } + only_phi = 0; + break; + default: + only_phi = 0; + break; + case iro_Phi: + for (j = get_irn_arity(irn) - 1; j >= 0; --j) { + ir_node *pred = get_irn_n(irn, j); + node_entry *pe = get_irn_ne(pred, env); + + if (pe->pscc != e->pscc) { + /* not in the same SCC, must be a region const */ + if (! is_rc(pred, header)) { + /* not a memory loop */ + goto fail; + } + if (! out_rc) { + out_rc = pred; + ++num_outside; + } else if (out_rc != pred) { + ++num_outside; + } + } + } + break; + } + } + if (! process) + goto fail; + + /* found a memory loop */ + DB((dbg, LEVEL_2, " Found a memory loop:\n ")); + if (only_phi && num_outside == 1) { + /* a phi cycle with only one real predecessor can be collapsed */ + DB((dbg, LEVEL_2, " Found an USELESS Phi cycle:\n ")); + + for (irn = pscc->head; irn; irn = next) { + node_entry *e = get_irn_ne(irn, env); + next = e->next; + e->header = NULL; + exchange(irn, out_rc); + } + env->changes |= DF_CHANGED; + return; + } + + /* set the header for every node in this scc */ + for (irn = pscc->head; irn; irn = next) { + node_entry *e = get_irn_ne(irn, env); + e->header = header; + next = e->next; + DB((dbg, LEVEL_2, " %+F,", irn)); + } + DB((dbg, LEVEL_2, "\n")); + + move_loads_out_of_loops(pscc, env); + +fail: + ; +} /* process_loop */ + +/** + * Process a SCC. + * + * @param pscc the SCC + * @param env the loop environment + */ +static void process_scc(scc *pscc, loop_env *env) { + ir_node *head = pscc->head; + node_entry *e = get_irn_ne(head, env); + +#ifdef DEBUG_libfirm + { + ir_node *irn, *next; + + DB((dbg, LEVEL_4, " SCC at %p:\n ", pscc)); + for (irn = pscc->head; irn; irn = next) { + node_entry *e = get_irn_ne(irn, env); + + next = e->next; + + DB((dbg, LEVEL_4, " %+F,", irn)); + } + DB((dbg, LEVEL_4, "\n")); + } +#endif + + if (e->next != NULL) { + /* this SCC has more than one member */ + process_loop(pscc, env); + } +} /* process_scc */ + +/** + * Do Tarjan's SCC algorithm and drive load/store optimization. + * + * @param irn start at this node + * @param env the loop environment + */ +static void dfs(ir_node *irn, loop_env *env) +{ + int i, n; + node_entry *node = get_irn_ne(irn, env); + + mark_irn_visited(irn); + + node->DFSnum = env->nextDFSnum++; + node->low = node->DFSnum; + push(env, irn); + + /* handle preds */ + if (is_Phi(irn) || is_Sync(irn)) { + n = get_irn_arity(irn); + for (i = 0; i < n; ++i) { + ir_node *pred = get_irn_n(irn, i); + node_entry *o = get_irn_ne(pred, env); + + if (irn_not_visited(pred)) { + dfs(pred, env); + node->low = MIN(node->low, o->low); + } + if (o->DFSnum < node->DFSnum && o->in_stack) + node->low = MIN(o->DFSnum, node->low); + } + } else if (is_fragile_op(irn)) { + ir_node *pred = get_fragile_op_mem(irn); + node_entry *o = get_irn_ne(pred, env); + + if (irn_not_visited(pred)) { + dfs(pred, env); + node->low = MIN(node->low, o->low); + } + if (o->DFSnum < node->DFSnum && o->in_stack) + node->low = MIN(o->DFSnum, node->low); + } else if (is_Proj(irn)) { + ir_node *pred = get_Proj_pred(irn); + node_entry *o = get_irn_ne(pred, env); + + if (irn_not_visited(pred)) { + dfs(pred, env); + node->low = MIN(node->low, o->low); + } + if (o->DFSnum < node->DFSnum && o->in_stack) + node->low = MIN(o->DFSnum, node->low); + } + else { + /* IGNORE predecessors */ + } + + if (node->low == node->DFSnum) { + scc *pscc = phase_alloc(&env->ph, sizeof(*pscc)); + ir_node *x; + + pscc->head = NULL; + do { + node_entry *e; + + x = pop(env); + e = get_irn_ne(x, env); + e->pscc = pscc; + e->next = pscc->head; + pscc->head = x; + } while (x != irn); + + process_scc(pscc, env); + } +} /* dfs */ + +/** + * Do the DFS on the memory edges a graph. + * + * @param irg the graph to process + * @param env the loop environment + */ +static void do_dfs(ir_graph *irg, loop_env *env) { + ir_graph *rem = current_ir_graph; + ir_node *endblk, *end; + int i; + + current_ir_graph = irg; + inc_irg_visited(irg); + + /* visit all memory nodes */ + endblk = get_irg_end_block(irg); + for (i = get_Block_n_cfgpreds(endblk) - 1; i >= 0; --i) { + ir_node *pred = get_Block_cfgpred(endblk, i); + + pred = skip_Proj(pred); + if (is_Return(pred)) + dfs(get_Return_mem(pred), env); + else if (is_Raise(pred)) + dfs(get_Raise_mem(pred), env); + else if (is_fragile_op(pred)) + dfs(get_fragile_op_mem(pred), env); + else { + assert(0 && "Unknown EndBlock predecessor"); + } + } + + /* visit the keep-alives */ + end = get_irg_end(irg); + for (i = get_End_n_keepalives(end) - 1; i >= 0; --i) { + ir_node *ka = get_End_keepalive(end, i); + + if (is_Phi(ka) && irn_not_visited(ka)) + dfs(ka, env); + } + current_ir_graph = rem; +} /* do_dfs */ + +/** + * Initialize new phase data. We do this always explicit, so return NULL here + */ +static void *init_loop_data(ir_phase *ph, const ir_node *irn, void *data) { + (void)ph; + (void)irn; + (void)data; + return NULL; +} /* init_loop_data */ + +/** + * Optimize Loads/Stores in loops. + * + * @param irg the graph + */ +static int optimize_loops(ir_graph *irg) { + loop_env env; + + env.stack = NEW_ARR_F(ir_node *, 128); + env.tos = 0; + env.nextDFSnum = 0; + env.POnum = 0; + env.changes = 0; + phase_init(&env.ph, "ldstopt", irg, PHASE_DEFAULT_GROWTH, init_loop_data, NULL); + + /* calculate the SCC's and drive loop optimization. */ + do_dfs(irg, &env); + + DEL_ARR_F(env.stack); + phase_free(&env.ph); + + return env.changes; +} /* optimize_loops */ + /* * do the load store optimization */ void optimize_load_store(ir_graph *irg) { walk_env_t env; + FIRM_DBG_REGISTER(dbg, "firm.opt.ldstopt"); + assert(get_irg_phase_state(irg) != phase_building); assert(get_irg_pinned(irg) != op_pin_state_floats && "LoadStore optimization needs pinned graph"); - if (! get_opt_redundant_loadstore()) - return; + /* we need landing pads */ + remove_critical_cf_edges(irg); edges_assure(irg); @@ -1197,6 +1766,8 @@ void optimize_load_store(ir_graph *irg) { /* now we have collected enough information, optimize */ irg_walk_graph(irg, NULL, do_load_store_optimize, &env); + env.changes |= optimize_loops(irg); + obstack_free(&env.obst, NULL); /* Handle graph state */